JPS61176628A - Nylon 6-4 having high molecular weight and production thereof - Google Patents

Abstract

PURPOSE:To produce a nylon 6.4 having high melting point, whiteness and molecular weight, by prepolymerizing hexamethylenediamine with succinic acid at a specific temperature, and carrying out the solid-phase polymerization of the obtained prepolymer. CONSTITUTION:Hexamethylenediamine and succinic acid are subjected to the prepolymerization at 150-300 deg.C, preferably 190-230 deg.C under pressure (preferably 5-20kg/cm<2>.G), and the resultant prepolymer is polymerized in solid phase at 180-280 deg.C, preferably 200-260 deg.C to obtain the objective polymer. The ratio of the diamine to the succinic acid used as the raw materials is selected to give a prepolymer having nearly equal amount of the terminal -NH2 group and -COOH group. USE:Material for connector, coil bobbin, or under-hood part for automobile.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to electrical and electronic parts and automobile parts.

[Prior art and its problems]

Nylon 6.4 has a higher melting point than general-purpose nylons such as nylon 6 and nylon 66, and is a polymer that has long been attracting attention. However, the heat stability of the raw material succinic acid in Nine No. 6 is extremely poor (it becomes succinic anhydride relatively easily at temperatures above 230°C, stopping the polymerization reaction, and is strongly colored. However, there was a problem in that the molecular weight did not increase.

To deal with the slippage, N,N'-hexamethylene disuccinimide was first synthesized and exposed under pressure at 200 tl. --P
art A-1vol, 5.15-20 (1967)
) and trichloride.

A method has been proposed in which a diamine and a dicarboxylic acid are polymerized in a pyridine solution of phosphorus. P (Unexamined Japanese Patent Publication No. 1973-
75794). However, in these methods, N,
A process for producing and purifying N'-hexamethylene disuccinimide is required, a process for recovering and purifying the pyridine solution is required, and the industrial utility value is inevitably lowered.

The inventors of the present invention have focused on the fact that there is no known method for producing white nylon 6.4 with high molecular weight and high industrial utility value, and have completed the present invention after intensive study.

[Structure and effect of the invention]

In the present invention, when producing nylon 6.4 from hexamethylene diamine and succinic acid,
Provided are high molecular weight nylon 6.4 obtained by prepolymerizing under pressure at a temperature of 0°C and in-phase polymerization of the obtained prepolymer at a temperature of 180°C to 280°C, and a method for producing the same.

The present invention also provides materials for electrical and electronic parts and materials for automobile underhood parts that have excellent properties and can be obtained by using nylon 6.4 or a resin composition containing it as a main component.

The amounts of hexamethylene diamine and succinic acid used in the present invention are determined so that the terminal -NH, and -COOH groups of the prepolymer are approximately equal.

Under temperature and pressure conditions that increase the escape of sheaquin,
It is desirable to add the diamine in an excess of 0.1 to 5.0 molar. Furthermore, the hexamethylene diamine and succinic acid used in this prepolymerization reaction may be purified solids in the form of salts, or may be used in the form of aqueous solutions of salts. In the case of an aqueous solution, it is desirable to concentrate it to 70% by weight or more before subjecting it to a prepolymerization reaction.

In the prepolymerization reaction, the reaction temperature is 150°C ~
3'00°C is adopted. The preferred temperature range is 170
℃~280℃, more preferably 190℃~230℃
It is ℃. If the reaction temperature is lower than 150°C, the reaction will not proceed, and if it exceeds 300 tl:ft, the condensation polymerization reaction will stop due to decomposition of succinic acid. The thermal stability of this succinic acid is nylon 66, nylon 6101, nylon 61
2. It is significantly worse than hexamethylene diamine, adipic acid, sepacic acid, dodecanedioic acid, and diaminobutane used in Nylon 46, and it is not a preferable method to react at high temperature for a long time.

In addition, during this prepolymerization, pressure is preferably applied to prevent the diamine from escaping, and the pressure is preferably 5 to 20 Kq.
It is best to set the pressure to /c++i-G.

In the solid phase polymerization reaction, a temperature range of 180°C to 280°C is preferred. At temperatures below 180°C, the reaction does not proceed, while at temperatures above 280°C, the polymer becomes noticeably colored. A more preferable temperature range is 200°C to 260°C.

At this time, it is desirable that the polymer be in an inert gas atmosphere. The reaction time is determined by the desired molecular weight, but if it exceeds 12 hours, coloration will become intense, which is undesirable.Also, the prepolymer to be subjected to solid phase polymerization may be in the form of pellets, powder, or Izu J-IFs. Seihaku IA presentation 'jP
11. - Minutes and 100 minutes are more preferable.

As described above, the present invention is an industrial manufacturing method that eliminates side reactions, and the polymer obtained by the present invention has a high molecular weight, a high melting point, and is a nylon 6-based polymer with excellent whiteness.
It is 4.

As described above, the present invention provides an industrially excellent method for producing nylon 6.4 and a nylon 6.4 with a high molecular weight, high melting point, and high whiteness obtained by this production method. Further, by taking advantage of the characteristics of nylon 6.4 produced by the present invention, connectors, coil bobbins, or automobile underhood parts having particularly excellent properties are provided. These products can be obtained by molding nylon 6.4 obtained according to the present invention or a resin composition containing nylon 6.4 as a main component by a known method.

[Example-1] 40 weight of salt of hexamethylene diamine and succinic acid
An aqueous solution containing (SORR) was charged into a t-1200m autoclave and concentrated at 180°C for 90 minutes.

At this time, the pressure was adjusted to eKg/dG.

After the concentration was completed, the temperature was raised to 200°C, and the reaction was carried out at this temperature for 2 hours. Also, the pressure at this time is 10 Kt/s!・G
Met. After the reaction was completed, the polymer was cooled in water, pulverized, and subjected to solid phase polymerization.

Solid phase polymerization was carried out using a rotary evaporator at 250
℃ for 4 hours. At this time, N2 was flowed at a flow rate of 1yo/min. After the reaction was completed, it was cooled and the polymer was taken out.

The resulting polymer was a white solid with ηr (1 wt, 95.5 h) I, 804) = 3.0, melting point 286°C.

Claims (1)

[Claims] 1. Hexamethylene diamine and succinic acid at 150°C
High molecular weight nylon 6.42 obtained by prepolymerizing under pressure at a temperature of 300°C and solid phase polymerization at a temperature of 180°C to 280°C, from hexamethylene diamine and succinic acid. , when producing nylon 6.4, prepolymerization is carried out under pressure at a temperature of 150°C to 300°C, and the obtained prepolymer is 18
Method 3 for producing high molecular weight nylon 6/4, characterized by solid phase polymerization at a temperature of 0°C to 280°C, hexamethylene diamine and succinic acid are subjected to solid phase polymerization at a temperature of 150°C to 280°C.
High molecular weight nylon 6.4 obtained by prepolymerizing under pressure at a temperature of 300°C and solid phase polymerization of the obtained prepolymer at a temperature of 180°C to 280°C, or a resin composition containing this as a main component. Materials for connectors, coil bobbins or automotive underhood parts